Umbrella review of international evidence for the effectiveness of school-based physical activity interventions

Background Obesity and physical inactivity among children and young people are public health concerns. Despite the wide variety of interventions available to promote physical activity, little is known about which interventions are most effective. This review aimed to evaluate the existing literature on school-based interventions that aim to increase physical activity among children and young people aged 6 to 18 years. Methods A systematic review of reviews was undertaken. We searched for systematic reviews and meta-analyses published between December 2017 and January 2024 using databases such as PubMed, Scopus, and CINAHL. Titles and abstracts were independently screened by two reviewers, who also conducted data extraction and quality assessments. We focused on outcomes like changes in physical activity levels and body mass index to assess the effectiveness of the interventions. Results A total of 23 reviews examining school-based physical activity interventions met the inclusion criteria, comprising 15 systematic reviews and 8 meta-analyses. All reviews (N = 23) were implemented in the school setting: three in primary schools, seven in secondary schools, and thirteen targeted both primary and secondary schools. The findings demonstrated that six reviews reported a statistical increase in physical activity levels among the target population, and one review found a decrease in body mass index. The most promising interventions focused on physical activity included within the school curriculum and were characterised as long-term interventions. 20 out of 23 reviews assessed the quality of primary studies. Conclusion Some interventions were promising in promoting physical activity among school-aged children and young people such as Daily Mile, Active Break, and Active transport while multi-component interventions seem to be positively effective in reducing BMI. Future efforts should focus on long-term, theory-driven programmes to ensure sustainable increases in physical activity.

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This statement is required for submission and will appear in the published article if the submission is accepted.Please make sure it is accurate.This umbrella systematic review aims to update and provide a comprehensive overview of the latest studies on the effectiveness of school-based physical activity interventions to promote physical activity among children, and young people aged 6 to 18 years old worldwide.

Methods
An umbrella systematic review incorporating literature search and narrative synthesis was conducted to identify, evaluate, and synthesize relevant evidence from intervention studies conducted in school settings globally.This review was conducted in accordance with the PRISMA guidelines for systematic reviews.The review protocol was registered with the PROSPERO International Prospective Register of Systematic Reviews, under registration number CRD42023494953.

Formulation of Research Question
The PICO framework was considered to formulate the aim of this research by describing the population (P), intervention (I), comparison (C) and outcome (O), as summarised in Table 1 below.The value of the PICO framework is that it breaks down complex questions into simpler phrases that also form the inclusion and exclusion criteria (Fenton & Baxter, 2016).

Outcome
The primary outcome is the self-reported or objectively measured change in PA levels.Secondary outcome includes changes in Body Mass Index.

Inclusion and Exclusion Criteria
Ideally, including a large body of evidence is desirable because it provides more material from which to derive decisions.However, given the extensive volume and diversity of research on school-based physical activity interventions worldwide, we decided to conduct an umbrella review of relevant systematic reviews, which included primary studies on the effectiveness of these interventions.Consequently, we applied the following inclusion and exclusion criteria to select the most appropriate articles for inclusion in this umbrella review.Reviews involved participants between the ages (6 to 18 years).

Reviews discussing physical activity without incorporating an intervention
Studies that explored at least one intervention for increasing physical activity among the targeted population Studies published in Arabic or English language.

Literature Search Process
Systematic searches were conducted in PubMed/MEDLINE, Scopus and CINAHL.These databases were chosen not only because they are easily accessible but also because they contain a large volume of systematic reviews and meta-analysis, due to their public health scope.
Furthermore, we searched reference lists in included reviews to identify relevant studies.
Details of the search strategy are outlined in the (S1 Appendix of the S1 File).

Studies Selection
All records were exported to Mendeley reference manager software.Duplicate records and all studies whose titles or abstracts did not meet the inclusion criteria were excluded.Screening of studies was conducted by two independent reviewers and, titles and abstracts of records retrieved from searches were screened for inclusion, and any disagreement was resolved by discussion with a third reviewer.

Data Extraction
A standardised approach was used to extract data from the selected studies [13], including study details such as the author(s), publication year, title, design, the number of studies included in the reviews, descriptions of interventions, duration of interventions and follow-ups, and outcomes measured, including physical activity levels and BMI, along with the main findings.

Quality Assessment
To evaluate the methodological quality and assess the risk of bias within the included reviews, the updated AMSTAR 2 version was utilised for analysing systematic reviews and metaanalyses, adhering to the recommendations specified by [14].This tool enabled the systematic reviews to be classified based on their overall quality into four categories: high, moderate, low, or critically low.any disagreement was resolved by discussion with a third reviewer.

Results
This results section contains three main parts: the search outcome, data extraction and synthesis, and quality of included reviews.

Search Outcome
The

Review characteristics
A total of 23 studies met the inclusion criteria, comprising 14 systematic reviews, eight metaanalyses, and one scoping review that employed a systematic review methodology.The characteristics of these reviews are detailed in Supplemental

School-Based Interventions
Twenty-three studies were included in this umbrella review, and these studies were grouped according to age and intervention type.

Interventions for Children aged 6 to 12 Years
Seven reviews [20][21][22][23][24][25][26]   life whereas, one study reported a positive effect in the increase in school physical activity levels, and this effect was not found in the overall levels of PA or the reduction of sedentary behavior.The quality assessment revealed that one was good, one was poor and one was fair quality.

Interventions for Both Children and Adolescents aged 6 to 18 Years
Out of the twenty-three reviews, thirteen reviews [15-17, 28-37] considered interventions conducted in both primary and secondary schools for children and adolescents aged between 6 and 18 years.psychosocial effects after the intervention and the rest studies reported changes that were not significant.Moreover, the majority of reviewed studies were based on the theoretical models: Achievement Goal Theory and Self-Determination Theory.Therefore, their review demonstrated the significance of motivational processes for the implementation of PA and sport as a precursor of psychosocial changes highlighting the significance of strategies and the duration of interventions/programmes -ie the longer interventions also have a longer lasting impact on behaviour to maintain significant changes over time.The majority of included studies in review of [31] were rated as high quality with few being medium quality.

Geographically specific reviews
The Rural and urban settings: the systematic review and meta-analysis of [36] aimed to evaluate and compare the effect of rural and urban/suburban school-based PA interventions on total PA among youth.They included 33 studies, and the most common intervention component was PE as used 20 times and classroom-based interventions were used 16 times.In rural studies, the meta-analysis indicated that no statistical significance pooled intervention effect on total PA.In subgroup analysis, they found that the magnitude of the effect was consistently small.
The test of group differences was significant only when considering studies separated by design (RCT vs. non-RCT), Qb (38) = 4.97, p = 0.03, indicating a significant difference in effect size between interventions with an RCT design and interventions with a non-RCT design.
Therefore, in brief, their findings demonstrated that the pooled effect of all school-based interventions to increase total PA was statistically significant but small.When they analysed urban and suburban studies separately, the effect was also statistically significant but small.
When they analysed rural studies separately, findings demonstrated a null effect of schoolbased interventions to increase total PA.It should be noted that the quality of included studies is unknown since [36] did not assess the risk of bias for included studies.confidence interval 0.16 to 1.30, little to no decrease in sedentary time (MD -3.78 minutes/d, 95% CI -7.80 to 0.24, may improve PF recorded as maximal oxygen uptake (VO2max) (MD 1.19 mL/kg/min, 95% CI 0.57 to 1.82 and may result in a minimal decrease in BMI z-scores (MD -0.06, 95% CI -0.09 to -0.02.The overall quality of the included studies in the review of

Impact on MVPA and fitness:
[37] was as follows: 33 studies were moderate quality, and 56 studies were low quality.

Impact on HRQoL:
The meta-analysis conducted by [35], aimed to assess the effects of PA HRQoL score, 0.192 (0.077, 0.306) for physical well-being, 0.158 (0.080, 0.237) for psychological well-being.In brief, their results conclude that physical exercise improved overall HRQoL and several HRQoL domains, such as physical well-being, psychological wellbeing, autonomy and parent relation, and social support and peers.However, their findings indicate no positive effect of the exercise programs on the school environment domain.The risk of bias for the included studies in the review of [35] showed that six out of 17 were at high risk of bias, four studies were medium, and seven studies were at low risk of bias.

Quality Assessment of Included Reviews
The methodological quality of the included reviews was classified into four categories: high, moderate, low, or critically low overall quality.Seven reviews were of high quality, four reviews were of moderate quality, five reviews were of low quality, and seven reviews were critically low.Most reviews did not report on the sources of funding for the studies included, except one review [37].Also, most studies did not provide a list of excluded studies nor justify the exclusions, except for two reviews [16,23].Three out of the twenty-three reviews failed to assess the risk of bias in the included studies, and two of them did not consider the risk of bias in individual studies when interpreting/discussing the results [20,24,36].Furthermore, seven studies did not explain their selection of study designs for inclusion in their reviews [16-19, 28, 29, 31].Nine studies omitted the components of PICO in their research questions and inclusion criteria [17-20, 25, 26, 28, 33, 35], and the authors of seven studies did not perform duplication in study selection or data extraction [16,17,19,20,22,31,36].
Eight out of the twenty-three reviews conducted a meta-analysis.Four of these studies used partially appropriate methods for the statistical combination of results and assessed the potential impact of the risk of bias in the included studies on the results and evidence synthesis [19,22,34,36].The findings of the quality assessment are presented in Supplemental Table 3 (S3 Appendix in S1 File).

Discussion
The main purpose of this umbrella review was to comprehensively evaluate the effectiveness of school-based physical activity interventions among children and young people aged 6 to 18 years internationally.A total of 23 reviews were included, with seven reviews implemented in primary schools among children aged 6 to 11 years, three reviews implemented in secondary schools among adolescents aged 12 to 18 years, and thirteen reviews targeted both children and adolescents aged 6 to 18 years.Our ability to come to solid conclusions was limited because the quality of the systematic reviews or meta-analyses was low, or because, as mentioned in several reviews, the quality of the included studies was very weak.Nevertheless, a few approaches seem more hopeful in encouraging more physical activity than others.reported in their review that the behaviour of peers has a profound effect on young people's behaviour.
Both the methods and reporting of systematic reviews in the topic area could be improved.
For example, most reviews failed to report on the sources of funding for the studies included in the review.Also, most studies failed to provide a list of excluded studies and justify the exclusions.Three reviews out of 23 reviews failed to assess the risk of bias in included studies and two of them did not account for the risk of bias in individual studies when interpreting/ discussing the results [20,24,36].Nine studies did not include the components of PICO in the research questions and inclusion criteria.Despite this, it was difficult to draw concrete conclusions in light of the low quality of some included studies.Consequently, further highquality research is needed to determine the effectiveness of physical activity interventions.

Strengths and Limitations of Primary Studies Included in Reviews
The key strength of primary studies included in reviews is the range and diversity of programmes evaluated and the range of different outcome measures.In addition, eleven reviews included high to medium-quality primary studies.However, there were some limitations: firstly, the quality of primary studies in some reviews cited as a limitation by review authors.Further, some authors indicated that the primary studies included had a high risk of bias and were unclear in some cases [17,25,29,32,33,35,37].So, it is impossible to fully trust the conclusions of a systematic review if the primary studies were flawed.Secondly, related to the trade-off between evaluating "real world" programmes and the lack of rigorous RCTs -and the impossibility of blinding which means that depending on self-reported outcomes was problematic.

Strengths and Limitations of the Umbrella Review
The key strength of this umbrella review is that it is the first to systematically assess the most recent scientific evidence on school-based physical activity interventions to promote physical activity among children and adolescents around the world.Furthermore, an in-depth quality assessment was conducted using the latest version of the AMSTAR 2, a tool for assessing systematic reviews.In addition, bringing these findings together has provided a comprehensive picture of the school-based physical activity interventions that are most likely to increase school children's and adolescents' levels of physical activity.However, this umbrella systematic review has some limitations.Firstly, the searches were limited to studies published in English and Arabic language which may led to missing potentially relevant studies.Secondly, with consideration of the heterogeneity in primary studies designs in each review, different types of interventions, outcomes, duration and measures restricted to the potential synthesis of the findings from different reviews and to directly compare the effectiveness of different intervention types.

Implications of the Findings for Policy Makers and Schools
The findings of this umbrella review have shown that some with the following details: Initials of the authors who received each award • Grant numbers awarded to each author • The full name of each funder • URL of each funder website • Did the sponsors or funders play any role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript?• Did you receive funding for this work?Competing Interests Use the instructions below to enter a competing interest statement for this submission.On behalf of all authors, disclose any competing interests that could be perceived to bias this work-acknowledging all financial support and any other relevant financial or nonfinancial competing interests.This statement is required for submission and will appear in the published article if the submission is accepted.Please make sure it is accurate and that any funding sources listed in your Funding Information later in the submission form are also declared in your Financial Disclosure statement.View published research articles from PLOS ONE for specific examples.

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without limitations, please do so.For example: Data cannot be shared publicly because of [XXX].Data are available from the XXX Institutional Data Access / Ethics Committee (contact via XXX) for researchers who meet the criteria for access to confidential data.The data underlying the results presented in the study are available from (include the name of the third party • All relevant data are within the manuscript and its Supporting Information files.Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation and contact information or URL).This text is appropriate if the data are owned by a third party and authors do not have permission to share the data.• * typeset Additional data availability information: Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation Abstract: Background: Obesity and physical inactivity among children and young people are public health concerns.Despite the wide variety of interventions available to promote physical activity, little is known about which interventions are most effective.This review aimed to evaluate the existing literature on school-based interventions that aim to increase physical activity among children and young people aged 6 to 18 years.Methods: A systematic review of reviews was undertaken.We searched for systematic reviews and meta-analyses published between December 2017 and January 2024 using databases such as PubMed, Scopus, and CINAHL.Titles and abstracts were independently screened by two reviewers, who also conducted data extraction and quality assessments.We focused on outcomes like changes in physical activity levels and body mass index to assess the effectiveness of the interventions.Results: A total of 23 reviews examining school-based physical activity interventions met the inclusion criteria, comprising 15 systematic reviews and 8 meta-analyses.All reviews (N=23) were implemented in the school setting: three in primary schools, seven in secondary schools, and thirteen targeted both primary and secondary schools.The findings demonstrated that six reviews reported a statistical increase in physical activity levels among the target population, and one review found a decrease in body mass index.The most promising interventions focused on physical activity included within the school curriculum and were characterised as long-term interventions.Conclusion: Some interventions were promising in promoting physical activity among schoolaged children and young people such as Daily Mile, Active Break, and Active transport while multi-component interventions seem to be positively effective in reducing BMI.Future efforts Introduction The World Health Organization (WHO) identifies childhood obesity as a significant public health concern in the 21st century.In 2016, a staggering 41 million children below the age of five were reported to be overweight, predominantly residing in developing nations [1].Overweight and obesity are linked to various health repercussions that frequently manifest later in life.Consequently, children who are overweight or obese are at an increased risk of developing non-communicable diseases like diabetes, cardiovascular diseases, and metabolic syndrome in adulthood [2,3].One of the essential factors for preventing obesity encompasses maintaining proper engagement in regular physical activity.The World Health Organization advises that individuals aged 5-17 years should engage in a minimum of sixty minutes of moderate to vigorous intensity physical activity (MVPA) each day, with a primary focus on aerobic activities [4].Childhood overweight and obesity have been associated with adverse psychosocial outcomes, including issues such as poor self-image, low self-esteem, an elevated risk of developing eating disorders, and a diminished quality of life [5].The rising occurrence of childhood obesity for example in Europe can be attributed to societal and lifestyle shifts observed over the past three decades [6].These changes are marked by the adoption of unhealthy eating habits, characterized by a high consumption of unhealthy fats and added sugars, coupled with a reduced intake of complex carbohydrates and fiber.Additionally, a sedentary lifestyle, characterized by prolonged screen time and a lack of involvement in physical activities, has contributed to this trend [7].To the best of our knowledge, numerous programs have been developed to promote healthy lifestyles and prevent obesity in children.The predominant approach in the vast majority of these initiatives involves utilizing schools as the primary setting for implementing interventions targeted at school-aged children [8,9].Schools play a significant role in shaping the social environment for children, and various efforts have been undertaken to leverage this setting for promoting healthy behaviors among youth, encompassing physical activity habits [10,11].Programs implemented in schools can reach nearly all children, spanning various ethnic and socio-economic backgrounds.Moreover, schools can encourage physical activity through structured programs, with sports education being a compulsory component of the school curriculum.In many instances, children are also required to walk to and from school on weekdays [12].Consequently, schools serve as an ideal environment to implement PA interventions [10].Previous umbrella systematic review [9] synthesized evidence on interventions to increase physical activity among children and young people across various settings, with a significant focus on school-based programmes.It finds that interventions involving physical activity embedded within the school curriculum, long-term initiatives, teacher involvement, and family support show the most promise in enhancing physical activity levels.The review includes studies conducted in school, preschool, family, and community settings, highlighting the comprehensive scope of its analysis and the pivotal role of schools in promoting physical activity.
based on a search conducted from 2018 onwards because there was previously an umbrella review based on a search for studies published from January 2010 until November 2017 [9] search was conducted in January 2024.The initial literature search produced a total of 2365 studies: PubMed/MEDLINE 1359, Scopus 290 and CINAHL 716.There were 682 duplicates, and after their exclusion, the 1683 remaining records' titles and abstracts were screened against the inclusion and exclusion criteria.The full texts of the remaining 60 studies were screened which led to the exclusion of 35 studies.The main reasons for exclusion were (1) having an inappropriate target population (n=8); (2) being protocols (n=2); (3) not schoolbased (n=5); (4) measured different outcomes (n=17) and (5) did not adopt a systematic review approach (n=3).Further articles (n=4) were identified from reference lists of included reviews.Details on excluded studies can be found in the S2 Appendix in the S1 File.A PRISMA flow diagram shows search results (Fig 1).

Interventions for Adolescents aged 12 to 18 Years
Out of the twenty-three reviews, only three reviews[18,19,27]  investigated interventions conducted in secondary schools for adolescents aged between 12 and 18 years.Multi-component interventions:Buru and their colleagues reviewed three types of interventions: physical activity, sedentary behavior and nutrition.PA was used in 11 out of 13 reviewed studies, the shortest intervention was four months and the longest was two years with a follow-up of three years.They found that only two of the included studies reported a significant increase in active transport, in terms of change in PA.Furthermore, only four of the included studies reported a significant decrease in BMI, whereas eight studies did not find any significant changes in BMI.Furthermore, three included studies recorded a significant decrease in body fat and only one study reported a significant decrease in body weight for the intervention group as compared to the control group.Therefore, Buru and their colleagues thought that despite the weak evidence of intervention efficacy for most of the reviewed studies, school-based interventions with multi-component combinations of physical activity, nutrition, and alignment to a theory yielded promising results.The quality assessment of included studies revealed that 11 studies were of medium quality and two studies were of high quality.In the systematic review that was focused on only adolescent girls [19], most of their interventions were multi-component, four interventions were modified PE lessons and two were educational based, the shortest intervention was six months and the longest was three years.13 interventions were delivered by the school staff, two were delivered by instructors and two by research team.Ten included studies used accelerometers to measure PA, nine studies used self-report questionnaires and two studies combined self-report and accelerometers.Owen with their colleagues found that school-based interventions provided a small, but significant positive effect on PA levels among adolescent girls (k = 16, g = 0.07, p = 0.05).The quality assessment for included studies revealed that ten studies were classified as having a moderate risk of bias, six studies were weak, three were strong and one had a very strong risk of bias.Active breaks intervention:The systematic review conducted by [27], aimed to examine the impact of school-based physical activity interventions of "active breaks" on PA levels and other outcomes such as classroom behaviour, cognitive functions and well-being.They reviewed three studies about physically active lessons and active break interventions.Intervention periods varied from 11 weeks to 7 months.They found that two of the included studies demonstrated a positive effect of active breaks on students' classroom behavior and quality of review of [15] examined the effectiveness of interventions to promote PA among children and adolescents in Asian countries.They reviewed 30 studies, 21 included studies were schoolbased, and 16 studies were cluster RCT.Interventions ranged in duration from one day to 60 months (median 4.5 months).Their primary outcome was changed in PA and PA was assessed by device-based tools such as an accelerometer and pedometer in four studies, and the rest used self-reported such as questionnaires.17 included studies out of 30 used a theoretical framework/ model and eight studies used multiple intervention strategies including a combination of PA sessions, exercise, physical activities such as indoor-outdoor PA, aerobic dance, rope skipping activities and PE sessions.The other included studies used educational interventions.15 studies showed significant increases in PA behaviour or PF and these studies were of moderate-to-high quality.Their evidence also showed that single or multicomponent interventions for short-term (up to six months) including PA sessions, PE, and health education might increase overall PA in Asian children and adolescents.
The review of [37], investigated intervention effectiveness to increase MVPA and improve fitness.There were 89 included studies in the review representing 66,752 individuals.They reviewed 40 multi-component interventions, 19 school time PA, 15 enhanced PE, and 14 before and after school programs.The duration of interventions varied greatly from a minimum of 12 weeks to 6 years, with 10 studies reporting intervention periods of 3 years or longer.Their review showed that interventions based in schools may result in little to no increase in time engaged in MVPA (mean difference 0.73 minutes/d, 95% interventions on several domains of health-related quality of life (HRQoL) and to examine the effectiveness of interventions on the same domains.They reviewed 17 different interventions and most of them were adding extra (PE) lessons to the regular school curriculum with a few of them being short active breaks.Their meta-analysis indicated that pooled effect size (95% CI) estimates for the effect of PA on HRQoL were as follows: 0.179 (0.045, 0.002) for total Finally, adding extra (PE) lessons to the regular school curriculum with a few of them being short active breaks showed positive effect on several domains of health-related quality of life such as physical well-being and psychological well-being[35].Nevertheless, schools remain an important setting for promoting PA, since they interact more frequently with school-aged children during the first two decades of their lives than any other institution.Furthermore, as indicated by [42] youth's ability to increase their level of physical activity and sustain it may be heavily influenced by their social environment and their social support system.It is unlikely that someone will begin to walk to school if no one walks to school[42].Additionally,[31] interventions were promising in increasing physical activity levels in school children and adolescents such as the Daily Mile programme, active breaks, active desks, and multi-component interventions.Other interventions such as multi-component interventions concerned with PA, nutrition and education shown a potential to increase PA and decrease BMI.While effective programmes have been identified, their applicability may vary globally.Thus, future research should aim to enhance the quality of evidence and broaden the implementation context.Moreover, there is a need for more studies with robust designs, like rigorous randomised controlled trials, that have adequate sample sizes, proper control groups, sufficient follow-up periods extending well beyond the intervention, and that employ validated measures of PA and assess sustainability issues.Conclusion This umbrella review evaluated the literature on the effectiveness of school-based physical activity interventions for children and young people aged 6 to 18 years internationally.The Daily Mile, Active Break, and Active Transport interventions showed promise in enhancing PA levels, while multi-component interventions were effective in reducing BMI.Long-term interventions, supported by rigorous theoretical and methodological frameworks, also appeared to increase PA levels.However, the overall conclusions are tempered by the low quality of some studies, highlighting the need for further high-quality research to ascertain the true effectiveness of these interventions.

Table 2 ,
accessible in S3 Appendix in the S1 File.The majority of the reviews were international in scope, with only four reviews targeting specific regions: one focused exclusively on Asian countries [15], another on the Middle East and Arabic-speaking countries [16], a third on school children in Latin America [17], and a fourth on adolescents in Australia [18].All reviews included both males and females except one review which targeted only girls [19].
Overall, Breslin and colleagues concluded that sustained participation in the Daily Mile leads to increased MVPA and physical fitness among school-aged children, without significant impacts on academic performance or BMI.Only one study highlighted a short-term enhancement in mental health[23].Similar results were reported by[20].However, they also reported some implementation barriers for "The Daily Mile programme" such as repetitive nature, time constraints associated with competing curriculum demands, and inadequate facilities regularly necessitate the adaptation and development of the original Daily Mile intervention format by schools and teachers [20].It should be noted that Breslin et al review and Hanna et al review included largely the same primary studies and the quality assessment for included studies conducted by Breslin et al revealed that one study was excellent, six were good, five were fair and none of them was poor quality.One review [24], investigated universal interventions (n=178), 62 interventions were theory based and the duration on average was 44 weeks (Range: 1-410 weeks).146studies assessed the PA outcomes as 74 studies used accelerometers, 25 studies used pedometers, 58 used questionnaires and 8 studies used direct observation.141includedstudies in this review evaluated the effectiveness of the intervention on PA outcomes postintervention, and they recorded at least one significant intervention effect on measured PA, while 48 included studies did not show any significant increase in PA.In terms of long-term effectiveness, nine out of nineteen studies showed at least one significant intervention effect on measured PA, while ten studies did not indicate any intervention effect on the PA.In brief, Move physical activity and fitness intervention alongside a regular PE lesson" found favorable intervention effects on children's MVPA in all the studies, with a pooled effect of 14.3% higher lesson time in MVPA in the intervention groups, equivalent to around a 9-minute improvement in MVPA per 1 hour of PE lesson time.The range was from a 4% to 30% difference in the MVPA content of PE lessons.Evidence quality was generally high in this review.
concerned interventions conducted in the primary schools setting for children aged between 6 and 12 years.Daily Mile Programme: Two reviews [20,23] examined the effectiveness of this intervention, Breslin and their colleagues observed significant variability in outcomes across studies.althoughcomparingresultswaschallengingdue to the varied fitness tests used.Active-break intervention: Two systematic reviews[21,25], evaluated the effectiveness of this intervention, Carrasco-Uribarren et al, found a significant improvement in both PA and MVPA, levels.Six included studies in [25] review, recorded a significant increase in in-school PA (SMD = 0.46; 95% CI: 0.28, 0.64; I2: 52%).Furthermore, five studies recorded a significant increase in MVPA (MD = 3.20; 95% CI: 3.06, 3.35; I²: 0%), however, the reduction was not significant for sedentary behavior (SMD = −0.95;95%CI:−2.06,0.15;I²:98%).Masini and their colleagues also reported similar findings as they reported that Active-break interventions had a significant effect in increasing PA levels, MVPA and step count among primary school children and their meta-analysis demonstrated a statistically significant result for the step count very high.Furthermore, five RCTs in the review conducted by Masini and colleagues were poor quality, and 11 cohort studies were medium quality.Theory-based interventions:the review of [24] found a high percentage of effective interventions, some single-feature interventions were found to be effective while no specific feature combination seemed to be associated with better intervention effectiveness.Therefore, theory-based single as well as multi-feature interventions seem to have the potential to improve effectiveness concerning PA, CRF, and sedentary behaviour[24].It should be noted that the quality of the included studies in this review was unknown since the authors did not assess the risk of bias.Multi-component interventions: in the review of [26] most of their interventions (70%) were multi-component interventions and they found that interventions in children resulted in a small positive treatment effect in the intervention group compared to the control group (2.Physical education lessons: The last review of this age group [22] was to examine interventions to increase MVPA content in physical education.Their intervention "Born to with a conventional PE class, the duration ranged from four months to two years with a minimum follow-up of five months.They reported that above 60% of the included studies recorded a significant effect on at least one dietary/PA or obesity-related outcome, and five included studies reported a significant effect on physical condition tests and/or PA time.studiesmorefocused on PA, the success rate was 72.72% in eight out of 11 studies included and the success rate was found in only two included studies used PA as support.These findings refer to that PA-oriented interventions are more likely to be successful in the BMI variable.Furthermore, when the PA variable was examined, they found that PA levels of school children significantly increased in a proportion of the studies, and this success rate was achieved in studies focused on orientation and training.This result might show the significance of applying physical activity strategies as the focus of the intervention program to increase the levels of PA[28].It should be noted that 10 included studies were rated as strong quality whereas nine studies were moderate quality.lightPAand MVPA with an objective measurement.Regarding academic performance, only two studies that used upright active desks recorded an increase in the intervention group without any change in concentration.The overall quality of the included studies in the review of[33]was low. were concerning diet, education, and PA.The review of[17]was in Latin America and the review of[16]was in the Middle East and Arabic-speaking countries.[17]reviewed16interventions most of which targeted diet alone and two focused on PA compared a curriculum of PA programming on self-reported outcomes.They also reported that the studies with a follow-up period greater than three months reported sustained PA levels.It should be noted that most of the included studies (13 out of 16) in the review conducted [17] were weak quality.In the review of [16], 14 out of 17 studies had a low risk of bias.Single component interventions:in the review conducted by [28], they aimed to examine the possibility of school-based interventions for promoting PA and PF and preventing obesity.They reviewed 19 studies and most of the interventions were focused on physical activityrelated interventions including expanding the duration of PE or altering its content, performing extracurricular physical activities, participating in activities during breaks and lunch breaks, or providing activity breaks in classes other than PE.They recorded that when the BMI variable was examined in interventions.The quality assessment revealed that six included studies were high quality, four studies were medium and four were weak quality [30].Active desks: the review of [33], investigated the effects of active desks on sedentary behavior, PA, academic achievements, and overall health.They included 23 studies and active desks were in three forms: upright active desk, cycling desk and stability ball.One included study out of 23 found a significant difference in BMI for the interventional group compared to the control group after two years of intervention (−5.24 for BMI percentile) and other studies did not report any change.For sedentary behavior, two included studies noticed that when increase in MVPA between pre-and post-intervention.Furthermore, statistically significant increases were reported for standing time in nine included studies.For step counts, one study recorded an increase but without statistical analyses.For stepping time, one study reported an increase in Among the reviews that investigated interventions conducted in secondary schools for adolescents aged 12 to 18 years.Multicomponent interventions in two reviews[18,19]demonstrated a very small and nonsignificant effect on PA levels.These findings are in line with the previous umbrella review in the same field [9] as they reported that school-based interventions targeting adolescents do not have significant effects and are of questionable value.Owen et al suggest that during adolescence, complex physiological and psychological changes occur, which may complicate efforts to change behavior[19].The results of this review are consistent with those of previous studies that found that school-based interventions became successful when they had a duration of one school year or more and less successful in those that lasted less than six months [6].
home trip (Campos-Garzón et al., 2023).Therefore, active transport interventions may contribute 50% of the physical activity recommendations in school aged children on school days when both trip directions were actively performed.combine diet and PA produced greater benefits than single strategies alone [39-41].Furthermore, we found that a long-term intervention was another key component of effective interventions.Multi-component interventions demonstrated little to no increase in MVPA, little to no decrease in sedentary time, a minimal decrease in BMI and little improve in PF [37].